This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Piedmont Research Center / for Novartis -- 4 groups of animals, divided into manageable numbers for longitudinal imaging sessions, following a specific dosing/imaging/weighing/caliper measurement schedule: Day 1: Day of pair match and transfer of animals to Duke. Day 3: Imaging Day Day 4: Imaging Day Day 7: Imaging Day 8 Sampling Day. Tumors will be approximately 300 mg in size. Imaging will begin 2 hours after dosing and will be complete no more than 4 hours after dosing. Set up HRLN female nu/nu mice with 5x106 MDA-MB231 tumor cells in 0% Matrigel sc in mammary fat pad Cell Injection Volume is 0.2 mL/mouse implant cells into 5th mammary fat pad ( the right abdominal) Age at Start Date: 6-12 weeks Do a pair match when tumors reach an average size of 80 - 120 mg, and begin treatment Body Weight: days 1,3, 4, 7 Caliper Measurement: days 1,4,7